Surface roughness effects on the static and dynamic behaviour of squeeze film lubrication of short journal bearings with micropolar fluids

Abstract

The theoretical study of the effect of surface roughness on the squeeze film lubrication of short journal bearings with no journal rotation under fluctuating loads with micropolar fluids is made. A more general form of surface roughness is mathematically modelled by a stochastic random variable with non-zero mean, variance, and skewness. The generalized average Reynolds type equation is derived for the squeeze tilm lubrication of rough journal bearings with micropolar fluids as lubricant. The closed form expressions for the bearing characteristics are obtained. The cases of a constant applied load and an alternating applied load are analysed. Under a cyclic load the micropolar fluids provide a reduction in the journal centre velocity. Further, it is observed that, the presence of microstructure additives and the negatively skewed surface roughness on the bearing surface increases the load carrying capacity and decreases the journal centre velocity. © IMechE 2008.